Grade crossing guard



p 1941- G. c. BURNISON 2,255,911

GRADE CROSSING GUARD Filed May 2, 1958 INVENTOR George (C. lfiurnisonPatented Sept. 16, 1941 UNITED STATES A'lbl'i orsics 3 Claims.

My invention relates to improvements in grade crossings in which stopsare placed in each lane of trafiic and at either side of the crossingwhether the same is an arterial highway crossing, a railway or streetcar crossing, or any crossing of whatever nature in which a hazard tomotorists is created.

I provide pits in the highway and covers for the pits. I also providebarriers adjacent the pit that may be raised and lowered, as whendesired to prevent traffic passing along the highway at the crossings.

The primary purpose and object of my invention. is to provide a guard inthe lane of traffic to thereby minimize grade crossing dangers.

A further object of my invention is to provide at each grade crossingand in each lane of traffic, and at each side of the grade crossing,mechanical means for lessening the grade crossing hazards.

Heretofore it has been the general custom in America to provide onlyincomplete protection to the motorist at the grade crossings or toprovide a sign that indicates that a hazard is to be crossed or toprovide a gate or an under or an over crossing. If the latter two areemployed, great expense is created to thereby lessen the number of suchcrossings to be installed as protection to the motorists.

Through the use of my new and improved device adequate protection isprovided without the necessity for the great expense that is involved inthe making of over or under crossings. With the increase in traiiicspeeds and the density of motorized trafiic my device gives protectionto the motorist and to the railroad and arterial traific user and at anexpense that is within reach of the suppliers of the same.

With these and incidental objects in view, the invention consists ofcertain novel features of construction and combination of parts, theessential elements of which are set forth in the appended claims, and apreferred form of embodiment of which is hereinafter shown withreference to the drawing which accompanies and forms a part of thisspecification.

In the drawing:

Fig. I is a side view of a quick return trafnc barrier shown infragmentary sectional side View, and wherein the barrier is madeeffective by being raised above the surface of the highway to act as astop for vehicles.

Fig. II is a side view of the mechanism illustrated in Fig. I modifiedfor cyclical velocity characteristics different from those of Fig. I.

Like reference characters refer to like parts throughout the severalviews.

I have shown my device as beingdisposed within a pit or well I below thesurface of the highway with the primary top members 2 and 3 beingdisposed in surface alignment 4 of the pavement or roadway over whichany suitable vehicle as an automobile 5 is being operated. The pit I isplaced in the roadway and in a lane of traflic ofthe highway. These pitsare placed in each of the traffic lanes of the highway.

I place a prime mover such as an electric motor 6 within the pit andconnect the same with any suitable electric control mechanism placed onthe track over which the train is operated to energize the electricmotor through one cycle of the operation due to the passing of the trainover the track in either direction of the grade crossing.

The prime mover is mounted upon a support I which is normally raised bya plurality of coil springs 8 that are placed below the platform I andheld in place by any suitable fastening down bolts 8. A worm screw It issecured to the armature shaft II of the prime mover and the worm shaftis journaled with any suitable journal bearing HA that is mounted uponthe platform 1.

The worm Ill coacts with and drives a worm gear l2, and the worm gear I2is mounted upon any suitable shaft l3 and is journaled within suitablebearings not here shown. An elliptical gear I4 is mounted upon the shaftl3. A second shaft I5 is spaced apart from the shaft I3 and thelongitudinal center lines of the respective shafts l3 and I5 areparallel. The elliptical gear l4 coacts with and drives the ellipticalgear [6, and the shaft 15, upon which the gear i5 is mounted. The gearsl4 and it are like in diameter and the number of teeth disposedthereupon.

The coacting gear I! is mounted upon the shaft hi and the same coactswith and drives a gear 58. The gear 18 is mounted upon a shaft l9 and acrank 20 is mounted upon the shaft l9 or is formed integral therewithand a connecting rod 21 is actuated by the crank 20. The connecting rod21 is secured to a wrist pin 28 that is journaled within suitablebearings within a barrier block 29.

The barrier block 29 on one end is journaled about a shaft 3!! and inits raised position the abutting surface 3| of the barrier block israised within the pavement and acts as a stop over which the wheel orwheels of motor vehicles may not be driven when the block is in a raisedposition.

At each cycle of energization of the prime mover 6 the barrier block 29is raised from sur face alignment to create a barrier in the roadway andin the lane of traific in which the same is disposed.

The surface 32 of the barrier block 29 is normally disposed in surfacealignment with the plates 2 and 3 and with the road surface 4 and isonly raised at the time a car or train is being operated over therailway track at the crossing. The barrier is then electricallyenergized during the time the train is within the control of theelectric block for energizing the prime mover. At the completion of thecycle of operation, the barrier block 29 is in full retracted position.

In Fig. I the mechanism is shown in an intermediate position in theoperating cycle. Gears l1 and I8 are preferably made of equal diametersalthough they may be of unequal diameters as shown. when gears l1 and I8are of equaljdiameters, the elliptical gears l l and I6 provide aquick-return characteristic. If, in Fig.

I it is stated that the barrier 29 is in the rising part of acycle ofoperation, it will be evident that gear i6 is rotating at a lowerangular veloc ity than gear l4. After the barrier 29 has been raised toits highest position, further rotation of the mechanism occurs with theelliptical gears in such relative position that gear l6 rotates at ahigher angular velocity than gear l4 while the barrier 29 is beingretracted. This provides the desirable velocity characteristics inherentina mechanism which elevates the barrier 29 at a relatively low velocityand drops it quickly in retraction thereof. This is advantageous inoperation inasmuch as it is desirable for barrier 29 to be raised intoposition comparatively slowly to avoid prematurely placing an obstaclein the roadway, and it is desirable to drop the barrier as quickly aspossible once the necessity of its presence in the roadway has passed.

In Fig. II a modified form of actuating gear combination is shown for.raising and lowering a stop block 5|. The stop block 5| is hinged atone end as illustrated at 52 and is actuated by an eccentric arm 53 thatis actuated through a train of gears illustrated in dotted lines at 54,55, 56 and 51 through a worm 58 that is driven by an electric primemover 59.

The mechanism of Fig. II is differentiated from' that of Fig. I byhaving the connecting rod 53 operating the barrier 5|. For a quick riseand slower return, the direction of rotation of the prime ,mover needonly be reversed. In Fig. II the operation of the barrier is always in aone to one ratio with the elliptical gearing where- I as in Fig. I, theinterposition of gears l1 and [8 between the elliptical gears and thebarrier permits a ratio different from one to one if desired. a

While the form of mechanism herein shown and described is admirablyadapted to fulfill the object primarily stated, it is to be understoodthat it is not intended to confine the invention to the embodimentherein shown and described, as it is susceptible of embodiment invarious forms all coming within the scope of the claims which follow.

What I claim is:

1. In a grade crossing guard, the combination of a retractible barrierwhich can be raised as an obstruction in the way of vehicular traffic ina roadway, a prime mover for raising and lowering said barrier andgearing interposed between said prime mover and said barrier, saidgearing comprising a speed reduction gear, a pair of elliptical gears,and a connecting rod for lifting said barrier, the elliptical gearingrotating in a one to one ratio with the cycle of raising and loweringsaid barrier and angularly placed relative to said connecting rod tocause said barrier to be raised'at one speed and to be lowered at adifferent speed.

2. In a device of the class described, comprising a pit, a cover forsaid pit, with said cover being normally in alignment with the highwaysurface, said pit having a prime mover disposed therein, said primemover adapted for being energized from a remote control station, anarmature shaft adapted for being rotated when the prime mover isenergized, a worm connected to the armature shaft, a worm gear coactingwith the worm, said worm gear being mounted upon a shaft, a crank shaft,a train of gearing adapted for being driven by the worm wheel fordriving the crank shaft, a plurality of elliptical gears disposed insaid train of gears, a crank arm secured to and journaled relative tothe crank shaft, said cover being hingedly supported on its one end andadapted for being raised and lowered in through the action of the crankarm at each cythe pit, with said cover adapted. for being raised 1 abovethe surface of the highway and the top surface of the cover being innormal surface alignment with the surface alignment of the' highway,with one of the ends of the cover being curved and adapted for beingraised to place a hazard in the line of traffic of vehicles flowingthereover, an electric prime mover disposed within the pit, saidelectric prime mover adapted for being energized from a remote controlstation, a worm shaft secured to the armature shaft of the electricprime mover, a crank shaft disposed within the pit, a crank armconnecting the crank shaft with the cover, and a train of gearingdisposed between the worm and the crank shaft adapted for rotating thecrank shaft when the Worm is rotated, and a plurality of ellipticalgears disposed within said gear train.

GEORGE o. BURNISON.

